Apparatus for sharpening the cutters of drawing-pistons serving for manufacturing the grooves of barrels.



e. ENnf/i. SCHLAEPFER & A. ALTENBURGER.

mu PISTONS SERVING FOR 6 THE e'noovss OFBARR APPARATUS FOR-SHARPENING ms cumns or DRAW MANUFACTJURIN ELS.

APPLICATION FILED OCT-25. I915- Patented Nwfzl, 1916.

2 SHEETS-SHEEI If GfEND. A. SCI-ILAEPFER & ALTE NBURGER. APPAHATIIS FOR SHARPENING THE CUTTERS 0F DRAWING PISTONS SERVING FOR MANUFACTURING THE VGROOVES 0F BARRELS. I

APPLICATION FILED OCLZS. 1915- Patented Nov. 21, 1916.

2 SHEETS-SHEET 2.

' neonate.

GOTTHARID END, ARNOLD SCI-ILAEPFER', AND AUGUST ALTENBURGER, OF IFEUHAUSEN,

SWITZERLAND, ASSIGNORS TO THE FIRM: SGHAFT, 0F NEUHAUSEN, SWITZERLAND. I

SCHWEIZERISCHE INDUSTRIE-GESELL- APPARATUS FOR SHARPENING THE CUTTERS OF' DRAWING-PISTONS SERVING FOR MANUFACTURING THE GROOVES 0F BABJRELS. 1

Specification of Letters Patent. v Patented NQV. 213., 1916.

Application filed October 25, 1915. Serial No. 57,839.

To all whom it may concern:

Be 1t known that we, Go'r'rHARn END, AR- NOLD SCHLAEPFER, and AUGUST ALTENBUR- GER, citizens of the Republic of Switzerland,

all residing at- Neuhausen, Canton of Schaifhausen, Switzerland, have invented certain new and useful Improvements in Apparatus for Sharpening the Cutters of Drawing-Pie tons Serving for Manufacturing the Grooves of Ba'rrels; and we do hereby declare the following to be a full, clear, and exact description of .the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying -draw-.

ings, andto letters or figures of reference marked thereon, which form a part of this specification.

The sharpening of the cutters of drawing pistons for manufacturing the grooves of' gun-barrels has been hitherto performed by hand, which operation required very skilled workmen; But even the greatest exercise of skill inthis kind of work was not sufficient to Warrant the execution.

Theobject of the present inventioii is to devise an apparatus adapted to perform mechan'ically the sharpening of the cutters of such drawing pistons, i. e. an apparatus adapted to sharpen the cutters in a fixed manner and without the necessity of changing the position of the cutter-sin the drawing piston, so that they do not have to be taken out of the drawing piston. It is also of importance, that the piece, which,has to be sharpened, is alwaysfed inthe'proper manner into one of the several sharpening positions. According to the present invention this is effected by means of levers and a spring arrangement.

Two embodiments of our invention are shown by way of example in the accompanying drawings, in which Figures 1-5 illustrate the first embodiment. Fig. 1 shows an elevation partly in section; Fig. 2 shows a plan View of Fig. 1 and Figs. 3-5 show on an enlarged scale an elevation, a plan View and a section, respectively, of the cutters and a part of the drawing piston. Figs. 6-11 illustrate the second embodiment; F 1g. 6 shows a plan view; Fig. 7 shows a section on the line a perfect exactness in A-B of Fig. 6; Fig. 8 shows a part'of Fig.

6, partly on a horizontal section and Figs. 9-11 illustrate the sharpening device in different positions.

In the first embodiment of the invention 1 the slide 2 rests on a base-plate 1 and is adjustable in the horizontal direction To this slide there are fixed two supports 3 and at carrying two sliding pistons 5 and 6.-

Each piston is provided with a bore for the insertionof the drawing piston 7 on which are fixed cutters 8 and 8'. The fixing of the drawing piston is efiected by means of two chucks 9 and 10. To the above mentioned base plate 1 there is screwed acarrier consisting of three parts 11, 12, 13, :This

carrier (Eanbe adjusted, bymeans of three shafts'll', 12', and 13 in three-directions. On the uppermost part ofthis carrier there rests a bearing 14, in which rotates a grinding shaft 15.- The front end of the grinding shaft 15 carries a small grinding disk 16 tapering toward its'edge, In the middle of this shaft there is mounted adriving wheel 17 receiving its drive froma cord 18 (Figs.

1 and2).

The small cutters 8 and 8 have the courseof a helical line and the upper small cutters 8 are arranged transversely with regard to the lower cutters 8 The two small cutters 8 and 8 form" eacha single piece, and they are adjustably mounted in the drawingpi'ston (Figs. 35).

Tn order-to grind the cutters 8 and 8 exactly in accordance with their pitch it is means of a stop hook 22 engaging one of said notches, so that during the axial displace-' ment of the drawing piston 7 there is imparted a rotation to this piston 7 and to the small cutters. For the purpose of adjusting the slide 2 we provide a'scale 23 (Fig;

and this slide is kept in the proper vposition during the grindin operation by means of the two clamps 24 Figs. 1 and2).

For the purpose of sharpening the small 'cutters'8 and 8 the latter need not be taken out of the drawing piston, on the contrary the operator can leave these cutters 1n the vpiston, so that he can introduce them together with the. drawing piston into the sharpening apparatus. Upon the fixing or clamping of the drawing piston within the two pistons 5 .and 6 the grinding disk 16 is brought into the proper position with regard to one of the small cutters 8 or 8. As shown in Fig. 4 the grinding disk is set in such a manner, that it forms an angle with the small cutters; this is, however, not necessary. The shaft 15 is then rotated and the drawing piston 7 is shifted to and fro in an axial direction. Owing to the rotation imparted to this piston" 7 by the screw thread 19 pro- 1 vided onthe sliding piston 5 the cutter to be ground'is moved past the grinding disk 16 exactly in accordance with the cburse of its pitch'and it is thus sharpened. The nut is then turned through an angle of 180, whereupon the small cutter crossing the just sharpened one is sharpened in the same manner. By adjusting the slide 2 in the proper of the small cutters relatively to the stationary drawing piston or one of the two parts, i. e. the sharpening tool or the drawing piston, can carry out the axial movement while the other carries out the rotary movement.

According to the embodiment of the in I I 'vention shown in Figs. 6-11, in which corresponding parts have the same reference letters as in Figs. 15, there is screwed tightly to the base-plate 1 a guide'for a slide 2. To the slide 2 is rigidly connected the.

supports 3 and 4, which carry. the drawing piston 7 resting in the sliding pistons 5 and 6, said slide glides in the longitudinal direction within said guide. On the-base-plate 1 there are further mounted two .bearings 23,

1 and 24*, carrying the rod 25. Two springs 26 and 27 eflect in combination with the pro-- 1 jecti ng lug 28, a to and fro movement of the slide 2 either toward the right or the left, ac-

cording as the projecting lug 28 engages the ..recess 29 .or 30 On' the same slide 2 are mounted two pairs of bearings 31 and 32.

34 are 36, 37 and 38, respectively. The two supshown in Fig. 6), so that the spring 2 hereinbefore described 0n each of the corresponding shafts 33 and pivotally mounted two levers and ports 39 and 40, which are rigidly connected to the base-plate 1 serve as a support for the two adjustable stop screws 41 and 42. The heads of 7 these screws have the shape of toothed wheels, so that these screws can be independently adjusted by means of the hand wheels 43 and 44 in combination with the toothed wheels 45 and 46.

This apparatusworks as follows: Let us assume, that there has to be ground at first the surface 47 of'the small cutter. In this case the projecting lug 28 is brought into engagement with the recess 29 osition 7 moves the slide 2 toward the left, while the spring 26 is out of operation. The turned down lever-35 strikes against the stop screw 41 and remains in this position till the surface 47 is ground. Hereupon the lever 35 is turned upward and the spring 27 pushes the slide farther till the lever 36 touches the stop screw 41. This lever corresponds'with the surface 48 of the small cutter and said surface can therefore be ground. The projecting lug 28 stop 'screw 42,.so that also the surfaces 49 p and 50of the small cutter can be ground. vlZVhat we claim is 1. In an apparatus for sharpening the cutters of rdrawing pistons serving for manufacturing, the grooves of barrels, means for fixing theidrawing piston together with its cutters, a sharpening tool,

an adjustable carrier for the fixing means ent of the cutters for moving the drawing of the drawing piston and means independpiston and the sharpening tool in apositive manner relatively to one another in accordancewith the helical line shaped course of the cutters, substantially as described and as illustrated.

2. In an apparatus for sharpening the cutters of drawing pistons serving for manufacturing the grooves of barrels, two sliding chucks for fixing'the drawing piston, said chucks lying in the same axis and being adjustably mounted in the axial direction, a sharpening tool arranged between the sliding chucks, a screw-thread on one of these sliding chucks corresponding to the helical linejshaped course of the cutters and a nut, in which lies said last mentioned sliding chuck, the nut being rotatably and ad justably mounted and capable of being I. brought into two positions. at an angle of ,1

, substantially as described and as illustrated. f p

3. In an apparatus for sharpening the cutters of drawing pistons serving for" manufacturing the grooves of barrels, a sharpening tool, means for fixing the drawmg piston together with its cutters, means for moving the drawing piston and the sharpening tool in a positive manner relatively to one another in accordance with the helical line shaped course of the cutters and stops for determining'the difi'erenflgrinding positions of the drawing piston with regard to the sharpening tool, substantially as described and as illustrated.

4. In an apparatus for sharpening the cutters of drawing pistons serving for manufacturing the grooves of barrels, a sharpening tool, means for fixing the drawing piston together with its cutters, means for moving the drawing piston and the sharpening tool in a positive manner relatively to one another in accordance with the helical line shaped course of the cutters, a movable carrier for the fixing means of the drawing piston, stopping levers provided on said carrier and fixed stops acting together with said levers to determine the different grinding positions of the drawing piston with regard to the sharpening tool, substantially as described and as illustrated.

5. In an apparatus for sharpening the cutters of drawing pistons serving for manufacturing the grooves of barrels, a

' sharpening tool, means for fixing the drawing piston together with its cutters, means for moving the drawing piston and the sharpening tool in a positive manner relatively to one another in accordance with the helical line shaped course of the cutters, a

movable carrier for the fixing means'of the drawing-piston, reversible stop levers provided on said carrier, fixed stops working together with said stop levers to determine the difierent grinding positions of the drawing piston with regard to the sharpening tool and springs acting upon the carrier for the fixing means of the drawing piston to shift the drawing piston upon the reversal of a stop lever into the next'grinding position, substantially as described and as illus- .trated.

helical line shaped course of the cutters, a

movable carrier for the fixing means of the drawing piston, reversible stop levers provided on said carrier, stop screws acting together with said stop-levers to determine the different grinding positions of the drawing piston with regard to the sharpening tool and means for adjusting the stop screws, substantially as described and as illustrated.

7. In an apparatus for sharpening the cutters of drawing pistons serving for manufacturing the grooves of barrels, a

.said first mentioned toothed wheels and mounted on rotatable and adjustable shafts, substantially as described and as illustrated.

S. In an apparatus for sharpening the cutters of drawing pistons serving for manufacturing the grooves of barrels, a sharpening tool, means for fixing the drawing piston together with its cutters, means for moving the drawing piston and the sharpening tool in a positive manner relatively to one another in accordance with the helical line shaped course of the cutters, a movable carrier for the fixing means of the drawing piston, stops for determining the different grinding positions of the cutting piston, a projecting lug provided on an axially adjustable shaft, springs provided on this shaft and arranged on both sides of the projecting lug, notches in the carrier into which said lug may be introduced while one of said springs is tensioned, substantially as described and as illustrated.

In testimony that we claim the foregoing as our invention we have signed our names in presence of two subscribing Witnesses.

GOTTHARD END. ARNOLD SCHLAEPFER. AUGUST ALTENBURGER.

Witnesses:

ERNST FISCHER, CARL GUBLER. 

